Merged revision(s) 22056, 22377 from trunk/OpenMPT:

[Imp] Warn when Startrekker AM companion file for synthesized instruments is most likely missing.
........
[Imp] Allow Startrekker AM external sample check to also work for libopenmpt.
........
Merged revision(s) 22377 from trunk/OpenMPT:
[Imp] Allow Startrekker AM external sample check to also work for libopenmpt.
........



git-svn-id: https://source.openmpt.org/svn/openmpt/branches/OpenMPT-1.28@22385 56274372-70c3-4bfc-bfc3-4c3a0b034d27

soundlib/Load_mod.cpp

@@ -984,6 +984,7 @@ bool CSoundFile::ReadMOD(FileReader &file, ModLoadingFlags loadFlags)
 
 	// Reading patterns
 	Patterns.ResizeArray(numPatterns);
+	std::bitset<32> referencedSamples;
 	for(PATTERNINDEX pat = 0; pat < numPatterns; pat++)
 	{
 		ModCommand *rowBase = nullptr;
@@ -1091,6 +1092,8 @@ bool CSoundFile::ReadMOD(FileReader &file, ModLoadingFlags loadFlags)
 				if(m.instr != 0)
 				{
 					lastInstrument[chn] = m.instr;
+					if(isStartrekker)
+						referencedSamples.set(m.instr & 0x1F);
 				}
 			}
 			if(hasSpeedOnRow && hasTempoOnRow) definitelyCIA = true;
@@ -1212,7 +1215,7 @@ bool CSoundFile::ReadMOD(FileReader &file, ModLoadingFlags loadFlags)
 		m_nInstruments = 31;
 #endif
 
-		for(SAMPLEINDEX smp = 1; smp <= m_nInstruments; smp++)
+		for(SAMPLEINDEX smp = 1; smp <= GetNumInstruments(); smp++)
 		{
 			// For Startrekker AM synthesis, we need instrument envelopes.
 			ModInstrument *ins = AllocateInstrument(smp, smp);
@@ -1233,6 +1236,33 @@ bool CSoundFile::ReadMOD(FileReader &file, ModLoadingFlags loadFlags)
 			amData.Skip(120 - sizeof(AMInstrument));
 		}
 	}
+#endif  // MPT_EXTERNAL_SAMPLES || MPT_BUILD_FUZZER
+
+	if((loadFlags & loadSampleData) && isStartrekker && !m_nInstruments)
+	{
+		uint8 emptySampleReferences = 0;
+		for(SAMPLEINDEX smp = 1; smp <= 31; smp++)
+		{
+			if(referencedSamples[smp] && !Samples[smp].nLength)
+			{
+				if(++emptySampleReferences > 1)
+				{
+#ifdef MPT_EXTERNAL_SAMPLES
+					mpt::ustring filenameHint;
+					if(file.GetOptionalFileName())
+					{
+						const auto filename = file.GetOptionalFileName()->GetFilename().ToUnicode();
+						filenameHint = mpt::format(U_(" ({}.nt or {}.as)"))(filename, filename);
+					}
+					AddToLog(LogWarning, mpt::format(U_("This Startrekker AM file is most likely missing its companion file{}. Synthesized instruments will not play."))(filenameHint));
+#else
+					AddToLog(LogWarning, U_("This appears to be a Startrekker AM file with external synthesizes instruments. External instruments are currently not supported."));
+#endif  // MPT_EXTERNAL_SAMPLES
+					break;
+				}
+			}
+		}
+	}
 #endif // MPT_EXTERNAL_SAMPLES || MPT_BUILD_FUZZER
 
 	// Fix VBlank MODs. Arbitrary threshold: 8 minutes (enough for "frame of mind" by Dascon...).